Lists are an example of a data abstraction.

A data abstraction can often contain different types of elements. It also provides a separation between the abstract properties of a data type (integer, boolean, string) and the concrete details of its representation. Basically, it doesn’t matter that the type are different!

Create an empty list. Append the integer 3, a string of "hello" and a boolean of False into the list. Print out each index individually. Now, remove the number 3 and False from the list.

Finally, print out the list again.

Use a physical stopwatch to record the length of time it takes to run the program. calculate the difference obtained by calls to the method system.currenttimemillis() just before the start of the algorithm and just after the end of the algorithm. calculate the difference obtained by calls to the method system.currenttimemillis() at the start of the program and at the end of the program so that the elapsed time includes the display of the result. use the value returned by the method system.currenttimemillis() just after the end of the algorithm as the elapsed time.